[Scribus] SVG import problem

I created an SVG image in Inkscape 0.43, and wanted to use it on our
local LUG's next poster, so I tried to import it into Scribus (1.2.2.1
Ubuntu 5.10)... most of the SVG is fine, but the corners of some of
the rectangles are screwed up.
The SVG itself is here:
http://www.warbard.ca/temp/Tux_Warhol_simple.svg
Here's what it looks like imported into Scribus:
http://www.warbard.ca/temp/Screenshot-Scribus_SVGproblem.png
Is this a bug in Scribus's SVG importing/handling, or something else?
Thanks - Scribus has become one of my favourite apps over the last few months!
Brian.